Creating a RAID Array¶

RAID arrays allow you to increase the working speed with disks and ensure the reliability of data storage. RAID allows you to combine several physical drives into one logical drive. You can learn more about RAID levels here.

Hardware RAID-controller¶

You can choose a server with a hardware RAID-controller during placing an order for renting a dedicated server. Hardware RAID is required for operation of server with several disks running VmWare ESXI. We usually use controllers manufactured by Broadcom (previously LSI, then Avago). You should select the Hardware Raid item in the Advanced filter section to order a server with a hardware RAID-controller:

You can check if a hardware controller is installed on the server using the command in Linux:

lspci | grep RAID

The controller type can be found in Device Manager on Windows OS.

To install the OS on a hardware RAID-array, go to the IPMI console of the server, reboot it and go to the WebBIOS of the RAID-controller and configure the required volumes there when the system boots. All the necessary documentation for these steps is usually available on the websites of controllers' manufacturers or on the Internet.

You should create the required number of RAID0 volumes from one disk if you need to forward each disk separately in a system with hardware RAID.

Software RAID¶

You can create a software RAID-array from several disks if the server does not have a special controller or the disks are presented in the system separately through the HBA-controller.

You can select HBA, RAID1, and RAID0 on a server with two identical disks. RAID0, RAID1, HBA for a server with four identical disks. HBA, RAID0, RAID10 and a pair of RAID1 for a server with two pairs of different disks, for example, a pair of SSD and a pair of HDD.

It is possible to create a software RAID-array through the hardware's management menu of the Invapi control panel during the system reinstallation..

An example of creating a RAID-array for servers with two identical disks:

An example of creating a RAID-array for servers with four identical disks:

An example of creating a RAID-array for servers with a pair of SSD and a pair of HDD:

• HBA - all disks will be independently represented in the OS. The OS will be installed on the smallest disk, or sda1.
• RAID 1 (mirroring) - the array includes several disks, the information on which is duplicated. RAID 1 provides increased data storage security: if one drive fails, all data is stored on the second drive. The disks will be collected into a unified volume via mdadm, on top of which LVM will run.
• RAID 0 level (mirroring) - the array includes several disks, the information on which is duplicated. RAID 1 provides increased data storage security: if one drive fails, all data is stored on the second drive. The disks will be collected into a unified volume via mdadm, on top of which LVM will run.
• RAID 10 level (striped mirror) is the result of forming a RAID 0 array of two (or more) RAID1 arrays. RAID 10 allows you to increase the fault tolerance of the data warehouse in case of a failure of one of the disks of each sub-array.